All 182 guidelines published by the American College of Gastroenterology, American Gastroenterological Association, British Society of Gastroenterology, Canadian Association of Gastroenterology, Crohn's and Colitis Foundation of America and European Crohn's and Colitis Organisation as of 2012 were reviewed.

The team found 19 IBD guidelines.

61% of the guidelines failed to comment on conflict of interest

Alimentary Pharmacology & Therapeutics

The research team noted that 89% of the guidelines graded the levels of evidence using seven different systems.

Of the 1070 recommendations reviewed, 23% cited level A evidence.

The researchers found that 28% cited level B, 36% were level C, and 13% were level D.

The mean age of the guidelines was 4 years.

In addition, 61% of the guidelines failed to comment on conflicts of interest.

The team observed that all 8 articles commenting on conflicts of interest had conflicts with 81% of authors reported an average 12 conflicts of interest.

Lastly, there were variations in the recommendations between societies.

Dr Feuerstein's team concludes, "Nearly half the IBD guideline recommendations are based on expert opinion or no evidence."

"Majority of the guidelines fail to disclose any conflicts of interest, and when commenting, all have numerous conflicts of interest."

"Furthermore, the guidelines are not updated frequently and there is a lack of consensus between societal guidelines."

"This study highlights the critical need to centralize and redesign the guidelines development process."